Oil Filter for a Motor Vehicle Gearbox

ABSTRACT

An oil filter of a transmission for motor vehicles has one filter housing, at least one inlet opening for unfiltered oil, at least one outlet opening for filtered oil. A filter medium is arranged in the oil flow between the at least one inlet opening and the at least one outlet opening. The filter housing is formed from two shells connected with one another, a lower shell and an upper shell, and features a second outlet opening.

FIELD OF THE INVENTION

The invention relates to an oil filter for a transmission for motor vehicles.

BACKGROUND

Known oil filters for motor or transmission oil feature a filter housing, which consists of two half shells connected with one another on the circumference and a clamped filter medium. The filter housing features one inlet chamber for unfiltered oil and one outlet chamber for filtered oil, whereas the inlet and outlet chambers are separated by the filter medium. With suction filters, the unfiltered oil is sucked through the filter medium, and thereby cleaned.

DE 197 35 445 A1 discloses an oil filter with a filter housing that is integrated into the oil pan of the transmission. The known oil filter features two chambers, namely one inlet chamber for unfiltered oil and one outlet chamber for filtered oil. The inlet chamber is formed on its underside through the bottom of the oil pan, while the outlet chamber is formed by a plastic half shell. A filter medium is clamped between the inlet chamber and the outlet chamber. The inlet opening for unfiltered oil is located at the bottom of the oil pan, while the outlet opening is formed through a spout of the upper plastic shell.

Problems of designing an oil filter may arise when there are special installation conditions, for example, if two outlet openings for the oil filter are necessary and, at the same time, there are mounting obstacles or only confined installation space is available.

SUMMARY OF THE INVENTION

It is a task of the present invention to take into account such problems of conventional oil filters through an appropriate design of the oil filter. Additional objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

The tasks of the invention are solved by the characteristics of advantageous designs according to the claimed invention.

In accordance with the invention, the housing features two half shells connected with one another, preferably made of plastic, namely a lower shell and an upper shell, whereas one inlet opening is located in the lower shell, and two outlet openings are located in the upper shell. The two outlet openings, the spacing of which from each other is indicated, are provided for different suction connections.

According to a preferred embodiment, a first chamber for unfiltered oil is formed by the lower shell, and a second and third chamber for unfiltered oil, each of which is allocated an outlet opening, is formed by the upper shell. Thus, the filter housing has one inlet chamber for unfiltered oil and two outlet chambers for filtered oil, whereas the filter medium overlays the inlet chamber. For the upper shell, given the two outlet chambers arranged next to each other, a larger width arises than that of the lower shell, which features only one inlet chamber.

According to a further preferred embodiment, the filter medium is clamped on the circumference between the inlet chamber in the lower shell and the first outlet chamber in the upper shell. The filter medium, for example a membrane, does not extend across the entire width of the upper shell, which results in a savings of material and costs.

According to a further preferred embodiment, both the lower shell and the upper shell have a circumferential flange for the firmly bonded connection of both shells, whereas a bridge flange is arranged between the two outlet openings and the circumferential flange of the upper shell, which clamps with sealing effect the filter medium between itself and the lower shell. This ensures that the filter medium is clamped around the area of the inlet chamber.

According to a further preferred embodiment, the bridge flange is connected with the upper shell through bars that are left between the flow-through openings. Two functions are achieved through this; i.e., on the one hand, the clamping of the filter medium between the upper shell and the lower shell and, on the other hand, the formation of a flow cross-section between the two outlet chambers in the upper shell.

According to a further preferred embodiment, an intermediate flange of the lower shell is allocated to the bridge flange of the upper shell. With the circumferential flange of the lower shell, the intermediate flange forms a continuous sealing layer for the clamping of the filter medium.

According to a further preferred embodiment, the filter housing in the area of the second outlet chamber features an installation height, reduced by the amount ΔH, vis-à-vis the installation height H in the area of the inlet chamber and the first outlet chamber. The lower shell features a recess in the area of the bridge flange, and runs from the bridge flange up to the outer flange, approximately to the flange layer. This gives rise to the mentioned reduction in the installation height below the second outlet chamber, i.e. below the second outlet spout.

According to a further preferred embodiment, the two outlet openings in the upper shell are formed as spouts. Thus, it is possible to produce a simple plug-in connector with the oil connection lines.

According to a further preferred embodiment, the oil filter is able to be operated as a suction filter for two oil pumps. The suction spouts of the oil pumps feature the same spacing as the outlet spouts of the filter housing, and thus may be installed relatively easily through plugs.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention is shown in the drawing and more specifically described below, whereas additional characteristics and/or advantages may arise from the description and/or the drawing. The following is shown:

FIG. 1 is an oil filter under the invention with two output spouts and a partially reduced installation height; and

FIG. 2 is a section in the area of level II-II in FIG. 1.

DETAILED DESCRIPTION

Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

FIG. 1 shows an oil filter 1, which is able to be used for transmissions of motor vehicles, and can be arranged in the area of an oil pan of the transmission, which is not shown. The oil filter 1 comprises a filter housing 2, which is constructed of two shells, namely a lower shell 3 and an upper shell 4. The lower shell 3 features a circumferential flange 3 a and an inlet opening 5, which is arranged in the lower area of the lower shell 3. The upper shell 4 likewise features a circumferential flange 4 a, which has a firmly bonded connection with sealing effect with the flange 3 a of the lower shell 3, for example by means of welding. In the upper shell 4, two outlet openings formed as spouts 6, 7 are arranged. With the upper shell 4, a bridge flange 8 is connected in one piece through bars 9. The lower shell 3 features a trough-like inlet chamber 10, which is limited upwards through a filter medium 11, preferably formed as a membrane. Through the upper shell 4, a first outlet chamber 12 and a second outlet chamber 13 are formed; these are in a flow connection with one another through the flow-through openings (see FIG. 2) between the bars 9. The first outlet spout 6 is allocated to the first outlet chamber 12, and the second outlet spout 7 is allocated to the second outlet chamber 13. The filter medium 11 is clamped between the lower shell 3 and the upper shell 4; on the one hand, between the circumferential flanges 3 a, 4 a, and on the other hand between the bridge flange 8 and a corresponding flange area 3 b of the lower shell 3, called the intermediate flange 3 b. The second outlet chamber 13 is closed by a floor 3 c, which is a part of the lower shell 3.

FIG. 2 shows a section in level II-II, marked in FIG. 1. The bridge flange 8 extends between the circumferential flange 4 a of the upper shell 4, and with the circumferential flange 4 a forms a continuous sealing layer. Analogously, the intermediate flange 3 b is molded on the lower shell 3; this passes into the outer areas of the circumferential flange 3 a. The filter medium 11 is clamped with sealing effect between the bridge flange 8 and the intermediate flange 3 b. Between the bars 9, which serve the purpose of reinforcing the bridge flange 8, the flow-through openings 14 are left, through which the filtered oil flows from the first outlet chamber 12 into the second outlet chamber 13.

The design of the filter housing 2 is intended for two separate suction connections, preferably two suction spouts of oil pumps that are not shown. The spacing of the output spouts 6, 7 marked with “a” in FIG. 1, is predetermined. This gives rise to a predetermined width for the filter housing 2. On the other hand, this width in the area of the lower shell 3 cannot be adhered to for installation reasons. The maximum installation height of the filter housing 2—without outlet spouts 6, 7—corresponds to the installation height of the inlet chamber 10 and the first outlet chamber 12, and is indicated in the drawing with H. In contrast, the installation height of the filter housing 2 in the left area of the drawing, i.e. within the floor 3 c of the second outlet chamber 13, is reduced by the dimension ΔH. Given the predetermined installation conditions, the filter housing 2 in this area may be left out; on the other hand, the predetermined distance a between the two outlet spouts 6, 7 was adhered to.

The lower shell 3 and the upper shell 4 are preferably made of plastic, and each are formed as molded parts.

The oil flow takes place—according to the flow arrows in FIG. 1—in the manner that initially unfiltered oil (which was collected in a pan that is not shown) enters through the lower inlet opening 5 into the inlet chamber 10, and is extracted from there upwards through the filter medium 11. Then, the filtered oil initially arrives in the first outlet chamber 12, from where the oil flow branches out: one part is extracted through the outlet spout 6 with a first pump, and another part flowing through the flow-through openings 14 (see FIG. 2) arrives in the second outlet chamber 13, and from there is extracted through the outlet spout 7 of a second pump. Thus, the oil filter 1 is preferably operated as a suction filter. The inlet opening 5 arranged in the floor area in FIG. 1 may also be provided in a side wall of the lower shell 3.

Modifications and variations can be made to the embodiments illustrated or described herein without departing from the scope and spirit of the invention as set forth in the appended claims. 

1-11. (canceled)
 12. An oil filter particularly suited for a motor vehicle transmission, comprising: a housing; an inlet opening defined in the housing; a first outlet opening defined in the housing; a filter medium disposed in the housing in an oil flow path between the inlet opening and the outlet opening; the housing defined by an upper shell member and a lower shell member connected together around a circumference of the shell members; and a second outlet opening defined in the housing.
 13. The oil filter as in claim 12, wherein the inlet opening is defined in the lower shell, and the first and second outlet openings are defined in the upper shell.
 14. The oil filter as in claim 13, further comprising an oil inlet chamber defined by the lower shell for unfiltered oil entering through the inlet opening, and a first filtered oil outlet chamber defined by the upper shell, the first outlet opening defined in the first filtered oil outlet chamber, and a second filtered oil outlet chamber defined by the upper shell, the second outlet opening defined in the second filtered oil outlet chamber.
 15. The oil filter as in claim 14, wherein the filter medium is clamped between the oil inlet chamber and the first filtered oil outlet chamber.
 16. The oil filter as in claim 12, wherein the upper shell and the lower shell each have a circumferential flange, the upper shell and the lower shell bonded together at the circumferential flanges, and further comprising a bridge flange defined across the oil flow path between the first outlet opening and the second outlet opening, the bridge flange extending transversely between the circumferential flanges.
 17. The oil filter as in claim 16, further comprising structure extending between the bridge flange and the upper shell member, the structure defining flow-through openings for oil flowing from the first filtered oil outlet chamber and the second filtered oil outlet chamber.
 18. The oil filter as in claim 17, wherein the bridge flange includes an intermediate flange defined by the lower shell member that extends transversely to the circumferential flange of the lower shell member.
 19. The oil filter as in claim 14, wherein the housing has a first installation height defined by the oil inlet chamber and the first filtered oil outlet chamber, the housing having a reduced second installation height defined by second filtered oil outlet chamber.
 20. The oil filter as in claim 19, wherein the second installation height is reduced by a height of the oil inlet chamber.
 21. The oil filter as in claim 12, wherein the first and second outlet opening are defined as spouts that extend from the upper shell member,
 22. The oil filter as in claim 12, wherein the first and second outlet opening are configured to mate with a suction side of different respective oil pumps. 